Cho $\Large \mathrm{log}_315=a, \mathrm{\log}_310=b.$ Giá trị biểu thứ

Cho $\Large \mathrm{log}_315=a, \mathrm{\log}_310=b.$ Giá trị biểu thức $\Large P=2+\log_{\sqrt{3}}50$

• A.

  A. $\Large 2a+2b.$

• B.

  B. $\Large 3a+2b.$

• C.

  C. $\Large 2a+2b-2.$

• D.

  D. $\Large 2a+3b.$

Chọn A

$\Large P=2+\mathrm{log}_{\sqrt{3}}50$ $\Large =2+2\mathrm{log}_3\bigg(\dfrac{15.10}{3}\bigg)$ $\Large =2+2\big(\mathrm{log}_315+\mathrm{log}_310-\mathrm{log}_33\big)$ $\Large =2+2(a+b-1)$ $\Large =2a+2b$